Of course;)
Look: In the replay, my Special Points (SP) are around 44, right? In the battle I described, Lethos had 51 SP. Without any agreements – that’s just how the map is. Accordingly, the Phoenix’s parameters were even higher. Out of all the Darkness spells, I only used Subjugation on the Leaders and Vampirism on the Phoenix in that battle. How would Anti-Darkness weaken these spells? Practically not at all. But Anti-Summon would severely reduce the Phoenix’s parameters and decrease its Shield. Besides the fact that the Shield would have less HP, the absorption would be 25% instead of 50% – a huge difference, wouldn’t you agree?
And I think it’s pointless to immediately level up 2 Slows. And Crippling won’t be as effective, and you’ll have to give up something else...
And regarding 2 Slows – think about it carefully! On such a long map, I think it’s quite justified.